Gentlemen,
A half hour later than my post just above, I started searching on this convertible top lubrication topic, and came across a result that was very good.
There are several different car make forums that this same topic has been approached. Some require you to register to get to the responses, and one seemed to sum things up with a lot of specific procedures and lubricants that show some expertise was used as well as logic.
Here it is:
DIY: Quiet Down Your Convertible Top and Prevent Mechanism Wear
The goal is noise reduction, along with making the top work with as little effort on the mechanism as possible. As the tops get old - the pivot points, which were greased at the factory - start to dry up, and this makes it harder for the motors to open/close the top. Eventually - this causes wear and failure of the motors and drive units, which gets expensive.
A properly lubrciated convertible top should open/close in under 30 seconds - so you can do it at the average traffic light.
But we also want to get rid of the creaking noises from the top - and that requires some selective lubrication of the top seals and mating parts.
General rules:
If it's rubber to rubber and one side has a fuzzy finish on it (flock) - you want it CLEAN and no lubricant on it.
If it's rubber to rubber and both sides are smooth - it needs some lubrication.
If it's rubber to glass or plastic or metal - and the rubber has fuzz on it - it should be CLEAN and not lubed.
If it's rubber to glass or plastic or metal - and the rubber is smooth (more common on the E36) - it should be lubed.
If it's metal to metal and it moves - it should be lubed.
Lubes I use:
All rubber parts - silicone grease. Dow Corning makes these for lots of purposes - I've used Dow Corning Silicone High-Vacuum Grease - a bit thicker than normal silicone grease, but works fine for this purpose. Silicone grease is not a good metal to metal grease - it is a good rubber to anything else grease and it protects the rubber from oxidation (due to ozone in the air.)
All metal pivot points - either a good lithium based grease (good for any sliding contact), or a decent synthetic motor oil (doesn't matter what kind or viscosity.. I use what I have around..)
How to lube:
To get access to all the top pivot points and spots that need lubrication, you'll need to partly lower the top, and move it to different positions. On some cars this can be done on battery power alone, on others - I'd suggest starting the engine to do it - it draws a lot of current and doing it repeatedly will end up with a discharged battery.
Applying the lithium based grease - usually this grease comes in a spray can with the little red tube that disappears into the darkest corner of your garage. The trick in using it - don't over spray on something that isn't supposed to get grease on it (like the top - inside or out.) Use old towels BEHIND whatever you're spraying if there is ANY chance of over spray getting on something you don't want.
Applying the motor oil - small drips of oil on pivot points works well. I use a small screwdriver dipped in the oil to carry a few drops to the point to be lubed. I then touch the tip of the screwdriver to the pivot in question and the oil is sucked off (capillary action) into the joint. AGAIN - put old towels under the pivot points if there is any chance of oil dripping on some of the fabric of the top.
Silicone grease - a fingertip is good. I squirt a bit on a fingertip and use my finger to get it exactly where I want it to go.
Gene
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